LIVONIA, MI â€“ Performance Engineering Group, a distributor for Raypak, saves the Calhoun County Justice Center upfront costs as well as heating and water capacity by designing a hybrid boiler system.
The Calhoun County Justice Center is a 192,000 ft˛ correctional facility in Michigan that houses both local inmates and those of other communities. While the basic mission of the facility's 630 inmate capacity is housing arrested and pre-trial inmates, their most important intention is to positively impact those who are incarcerated and, consequently, the community. The facility was experiencing failure of facility's two water heating units, unreliable system control, and tremendously low energy efficiency.
After inspection, Performance Engineering Group determined that the continuous water heating failures were in fact caused by a failed water treatment system rather than simply the heating units themselves. Any time the water treatment system would go off-line, the heating units were running with water high in Calcium and Magnesium which would create scale inside the water heaters and ultimately lead to system failing. In addition, Performance Engineering Group also determined that the boiler system and associated building pumps were grossly oversized resulting in excessive energy and water usage.
The Center's hefty heating system was reconfigured and replaced with two much smaller vertical Raypak XTherm® series condensing boilers. The new H7-1505 model boilers contain cutting edge modulation technology with an incredibly high 96% thermal efficiency rating! Plus with a 4:1 turndown ratio, the efficiency is maintained throughout the firing rate, lengthening equipment life and ensuring even more savings. With the high efficiency boilers in place, the water heating system was reconfigured and customized using dual, redundant heat exchangers to add the water heating load to the boiler heating loop. To provide for occupant safety a thermostatic mixing valve was added to the system. Given the reliability of the water treatment and the history of outages, Performance Engineering Group established that the custom-made indirect system would be more robust and dependable.
To increase system control, a TPC management system was added to the hybrid system. The Flow Intelligence® control measures the exact energy the system is using, and then modulates the boilers to replace only that energy. The patented technology includes hybrid intelligent load sharing which allows the two existing boilers and water heater to remain connected and act as back-up.
By utilizing the existing equipment in the hybrid system, the Center was able to save over $150K in upfront costs. Additionally, the payback on the investment of a hybrid system occurs more rapidly than an "all condensing" boiler system.
This Performance Engineering Group solution of system reconfiguration and equipment upgrade reduced the Calhoun County Justice Center's heating and water heating capacity by 83%! The energy savings not only impressively exceeded expectations but also generated opportunity for investment in additional energy conservation measures.